Tequilana weber Agave Bagasse Enzymatic Hydrolysis for the Production of Fermentable Sugars: Oxidative-Alkaline Pretreatment and Kinetic Modeling

As a way to mitigate the harmful effects of fossil fuel utilization, the use of second-generation ethanol has been proposed. However, the microorganisms responsible for its production are not able to degrade structural polysaccharides, so their hydrolysis is necessary. Previously to this work, a factorial experimental design was carried out to investigate the relation between the NaOH and H2O2 concentrations with the yield of carbohydrates, and then this variable was optimized by using a response surface method. A study of the hydrolysis process was performed using enzymes to establish a process that maximizes the depolymerization of Agave tequilana fibers after an alkali-oxidative pretreatment with optimal reagents concentrations, this pretreatment was selected because it can remove almost the total content of lignin and destroys efficiently the crystallinity of cellulose fibers with a lower sugar losses and no production of toxic compounds. An orthogonal array using the novel enzymes Cellic CTec 3 and Cellic HTec 3 was performed to determinate the optimal combination of them, which has resulted in a concentration of 165.67 g/L at the supernatant with 82.21 % conversion and a yield of 352.18 g reducing sugars per kilogram of lignocellulosic material in dry basis. These results are 29 % better in comparison with the previous generation of enzymes with a reduction in the enzymatic charge of 82 %.